Ethyl 2-acetyl-4-methyl-4-pentenoate is a known chemical entity. It has been described by T. F. Wood et al. [see J. Org. Chem. 28, 2248 (1963)] as a synthesis intermediate in a process for the preparation of certain aromatic musks. Its odorous properties however have remained so far unrecognized. I have now discovered that this ester possesses very useful fragrance characters and consequently it can be utilized in a wide range of applications.